公开(公告)号：US20230256414A1

公开(公告)日：2023-08-17

申请号：US18011540

申请日：2021-06-25

Applicant: BASF SE

Inventor： Sung Yeun CHOI ,  Andrey KARPOV ,  Christian WALSDORFF ,  Patrick HUBACH ,  Karl KHARAS

IPC: B01J21/04 ,  B01J35/10 ,  B01J23/50 ,  B01J6/00 ,  B01J37/02 ,  C07C29/50

CPC classification number: B01J21/04 ,  B01J35/1042 ,  B01J35/1047 ,  B01J23/50 ,  B01J6/001 ,  B01J37/0201 ,  C07C29/50

Abstract: A process for producing a porous alpha-alumina catalyst support, comprising i) preparing a precursor material comprising, based on inorganic solids content, at least 50 wt.-% of a transition alumina having a loose bulk density of at most 600 g/L, a pore volume of at least 0.6 mL/g and a median pore diameter of at least 15 nm; and at most 30 wt.-% of an alumina hydrate; ii) forming the precursor material into shaped bodies; and iii) calcining the shaped bodies to obtain the porous alpha-alumina catalyst support. The catalyst support has a high overall pore volume, thus allowing for impregnation with a high amount of silver, while keeping its surface area sufficiently large so as to provide optimal dispersion of catalytically active species, in particular metal species. The invention further relates to a shaped catalyst body for producing ethylene oxide by gas-phase oxidation of ethylene, comprising at least 15 wt.-% of silver, relative to the total weight of the catalyst, deposited on a porous alpha-alumina catalyst support obtained in the process described above. The invention also relates to a process for preparing a shaped catalyst body as described above comprising impregnating a porous alpha-alumina catalyst support obtained in the process described above with a silver impregnation solution, preferably under reduced pressure; and optionally subjecting the impregnated porous alumina support to drying; and b) subjecting the impregnated porous alpha-alumina support to a heat treatment; wherein steps a) and b) are optionally repeated. The invention further relates to a process for producing ethylene oxide by gas-phase oxidation of ethylene, comprising reacting ethylene and oxygen in the presence of a shaped catalyst body as described above.